Pillischer's "Lenticular Microscope" - Mr. J. Pillischer, of Bona Street, has most kindly presented this very interesting portable, really pocket, Microscope to the Society's Cabinet. It was designed by the late Mr. M. Pillischer, the donor's uncle.

The instrument is figured and described in Urinary Deposits by Golding Bird (p. 29, fig. 13, 1857, 5th ed.), but it will be noticed that the figure differs slightly from the original, inasmuch as a second spring to hold the slide has been added, and a semicircular segment cut out at both ends instead of at one end of the base-plate as there shown.

The design of this instrument (fig. 67) is most ingenious: there is neither stand nor limb, the main basis of the instrument being the slide- holder, at one angle of which is a short pillar containing a direct-acting screw fine adjustment, which acts upon a swinging arm carrying the lens. Below the stage is a mirror attached to a jointed arm, and a wheel of diaphragms. The lenses, three in number, are Coddingtons of 1/4, 1/10 and 1/25 -in. foci.

It may be pointed out, says E. M. Nelson, that an instrument of this kind, fitted with achromatic loups, would be very serviceable to a microscopist for field work.

It will be remembered that three of Dr. Gairdner's Microscopes, made by Bryson of Edinburgh, were exhibited, figured, and described in the journal for 1899, p. 643, fig. 149.

These had Coddington lenses, each power having a separate Microscope to itself. Gairdner's Microscope was described in the first edition of Carpenter on the Microscope, 1866, p. 74, fig. 15, and there it is said to be of use in bed-side investigations of urinary deposits.

In design, Gairdner's Microscope is far inferior to that of Pillischer's, inasmuch as there is no possibility of either moving the slide under the lens, or the lens over the slide, so nothing can be seen except the single point iu the axis of the lens.